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We studied the breeding parameters of a reintroduced population of individually marked Griffon Vultures Gyps fulvus in the Grand Causses region of southern France from the time of first reintroduction in 1982 to 1992. Among nesters, 65% of the birds released as immatures or born in the wild recruited into the breeding population when 4 years old, i.e. 1 year earlier than previously described. The proportion of birds nesting each year was relatively high and increased with time, suggesting that conspecific attraction favoured recruitment. We detected a permanent adverse effect of long-term captivity on the nesting success of birds released when more than 2 years old: compared to the natural population, birds which had been kept in captivity showed a reduced breeding success during the whole study period. The breeding success of released immatures and wild-born birds was similar to the highest values observed in a natural population in the Spanish and French Pyrenees. Breeding failures did not usually result in mate change but affected nest-site fidelity. Birds not born in the wild were more likely to recruit to the largest subcolonies available, which highlights the role of social attraction. The observed philopatry of wild-born birds probably resulted from such a social attraction since most of them were born in the largest subcolony. Conspecific attraction maintained the spatial aggregation of nests, whereas nest changes after a breeding failure favoured the spatial expansion of the colony.  相似文献   
2.
We isolated 45 new Kentish plover (Charadrius alexandrinus) microsatellite loci. These were tested for polymorphism in 42 Kentish plovers breeding in the Çukurova Delta, Turkey. Thirty‐six of the 45 loci were polymorphic with observed heterozygosity varying between 0.22 and 0.93. Genotypes of individuals of known sex indicated that two loci were sex‐linked (Calex‐26 is located on the Z chromosome and Calex‐31 on the W chromosome). Additionally, we tested all loci for amplification in four other species of Charadridae (Kittlitz's plover, Madagascar plover, three‐banded plover and white‐fronted plover). On average 34 loci amplified per species (range 29–36).  相似文献   
3.
1. The painted lady Vanessa cardui is a long‐range migratory butterfly that performs an annual multi‐generational round‐trip between Europe and Africa. Each autumn it returns to northwest (NW) Africa, presumably to track changes in resources that follow a predictable climate‐related spatio‐temporal pattern. 2. Data on the abundance of adult and immature stages in the Maghreb in 2014–2016 are used to test several hypotheses regarding the autumn migration of this species. 3. A strong seasonal migratory strategy was confirmed by the all but total absence of the species in NW Africa at the end of summer and the arrival of huge numbers migrants in October and November. Migration was timed to coincide with an increase in host plant availability but not with any increase in nectar sources. 4. Flower abundance was the main predictor of adult abundance in autumn, with Ditrichia viscosa, Verbesina encelioides, and Medicago sativa being key resources that attracted enormous numbers of butterflies to oases, ruderal habitats, and oueds. The distribution of immature stages was strongly predicted by host plant abundance (with traditional agriculture representing the most important breeding habitat) and latitude (most breeding occurred in the south of the region). Also, both adults and immature stages were more common inland than in coastal areas. 5. Changes in age structure of the adult population were also noted. The number of fresh adults slowly increased, indicating that butterflies did not return in a single wave and that the first offspring of the first returners were already emerging when some butterflies were still arriving.  相似文献   
4.
The stenopodaine genus Oncocephalus Klug, 1850 and two species of this genus, O. Breviscutum Reuter, 1882 and O. Pudicus Hsiao, are recorded from Cambodia for the first time.  相似文献   
5.
1. Prior to pupation, lepidopteran larvae enter a wandering phase lasting up to 30 h before choosing a pupation site. Because stillness is important for concealment, this behaviour calls for an adaptive explanation. 2. The explanation most likely relates to the need to find a suitable pupation substrate, especially in terms of shelter from predation, and given that many predators and parasitoids use host plants as prey‐location cues, mortality probably decreases with distance from the host plant. Hence, remaining on the host includes a long‐term risk, while moving away from the host introduces an increased risk during locomotion. 3. Bivoltine species that overwinter in the pupal stage produce two kinds of pupae; non‐diapausing pupae from which adults emerge after 1–2 weeks, or diapausing pupae that overwinter with adults emerging after 8–10 months. 4. Given the hypothesis of distance‐from‐host‐plant‐related predation, this should select for phenotypic plasticity with larvae in the diapausing generation having a longer wandering phase than larvae under direct development, if there is a trade‐off between mortality during the wandering phase and accumulated mortality during winter. 5. Here this prediction is tested by studying the duration of the wandering period in larvae of the partially bivoltine swallowtail butterfly, Papilio machaon, under both developmental pathways. 6. The results are in agreement with the predictions and show that the larval wandering phase is approximately twice as long under diapause development. The authors suggest that the longer duration of the wandering phase in the diapause generation is a general phenomenon in Lepidoptera.  相似文献   
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